1 /* Software floating-point emulation.
2    Basic eight-word fraction declaration and manipulation.
3    Copyright (C) 1997-2016 Free Software Foundation, Inc.
4    This file is part of the GNU C Library.
5    Contributed by Richard Henderson (rth@cygnus.com),
6 		  Jakub Jelinek (jj@ultra.linux.cz) and
7 		  Peter Maydell (pmaydell@chiark.greenend.org.uk).
8 
9    The GNU C Library is free software; you can redistribute it and/or
10    modify it under the terms of the GNU Lesser General Public
11    License as published by the Free Software Foundation; either
12    version 2.1 of the License, or (at your option) any later version.
13 
14    In addition to the permissions in the GNU Lesser General Public
15    License, the Free Software Foundation gives you unlimited
16    permission to link the compiled version of this file into
17    combinations with other programs, and to distribute those
18    combinations without any restriction coming from the use of this
19    file.  (The Lesser General Public License restrictions do apply in
20    other respects; for example, they cover modification of the file,
21    and distribution when not linked into a combine executable.)
22 
23    The GNU C Library is distributed in the hope that it will be useful,
24    but WITHOUT ANY WARRANTY; without even the implied warranty of
25    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
26    Lesser General Public License for more details.
27 
28    You should have received a copy of the GNU Lesser General Public
29    License along with the GNU C Library; if not, see
30    <http://www.gnu.org/licenses/>.  */
31 
32 #ifndef SOFT_FP_OP_8_H
33 #define SOFT_FP_OP_8_H	1
34 
35 /* We need just a few things from here for op-4, if we ever need some
36    other macros, they can be added.  */
37 #define _FP_FRAC_DECL_8(X)	_FP_W_TYPE X##_f[8]
38 #define _FP_FRAC_HIGH_8(X)	(X##_f[7])
39 #define _FP_FRAC_LOW_8(X)	(X##_f[0])
40 #define _FP_FRAC_WORD_8(X, w)	(X##_f[w])
41 
42 #define _FP_FRAC_SLL_8(X, N)						\
43   do									\
44     {									\
45       _FP_I_TYPE _FP_FRAC_SLL_8_up, _FP_FRAC_SLL_8_down;		\
46       _FP_I_TYPE _FP_FRAC_SLL_8_skip, _FP_FRAC_SLL_8_i;			\
47       _FP_FRAC_SLL_8_skip = (N) / _FP_W_TYPE_SIZE;			\
48       _FP_FRAC_SLL_8_up = (N) % _FP_W_TYPE_SIZE;			\
49       _FP_FRAC_SLL_8_down = _FP_W_TYPE_SIZE - _FP_FRAC_SLL_8_up;	\
50       if (!_FP_FRAC_SLL_8_up)						\
51 	for (_FP_FRAC_SLL_8_i = 7;					\
52 	     _FP_FRAC_SLL_8_i >= _FP_FRAC_SLL_8_skip;			\
53 	     --_FP_FRAC_SLL_8_i)					\
54 	  X##_f[_FP_FRAC_SLL_8_i]					\
55 	    = X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip];		\
56       else								\
57 	{								\
58 	  for (_FP_FRAC_SLL_8_i = 7;					\
59 	       _FP_FRAC_SLL_8_i > _FP_FRAC_SLL_8_skip;			\
60 	       --_FP_FRAC_SLL_8_i)					\
61 	    X##_f[_FP_FRAC_SLL_8_i]					\
62 	      = ((X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip]		\
63 		  << _FP_FRAC_SLL_8_up)					\
64 		 | (X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip-1]	\
65 		    >> _FP_FRAC_SLL_8_down));				\
66 	  X##_f[_FP_FRAC_SLL_8_i--] = X##_f[0] << _FP_FRAC_SLL_8_up;	\
67 	}								\
68       for (; _FP_FRAC_SLL_8_i >= 0; --_FP_FRAC_SLL_8_i)			\
69 	X##_f[_FP_FRAC_SLL_8_i] = 0;					\
70     }									\
71   while (0)
72 
73 #define _FP_FRAC_SRL_8(X, N)						\
74   do									\
75     {									\
76       _FP_I_TYPE _FP_FRAC_SRL_8_up, _FP_FRAC_SRL_8_down;		\
77       _FP_I_TYPE _FP_FRAC_SRL_8_skip, _FP_FRAC_SRL_8_i;			\
78       _FP_FRAC_SRL_8_skip = (N) / _FP_W_TYPE_SIZE;			\
79       _FP_FRAC_SRL_8_down = (N) % _FP_W_TYPE_SIZE;			\
80       _FP_FRAC_SRL_8_up = _FP_W_TYPE_SIZE - _FP_FRAC_SRL_8_down;	\
81       if (!_FP_FRAC_SRL_8_down)						\
82 	for (_FP_FRAC_SRL_8_i = 0;					\
83 	     _FP_FRAC_SRL_8_i <= 7-_FP_FRAC_SRL_8_skip;			\
84 	     ++_FP_FRAC_SRL_8_i)					\
85 	  X##_f[_FP_FRAC_SRL_8_i]					\
86 	    = X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip];		\
87       else								\
88 	{								\
89 	  for (_FP_FRAC_SRL_8_i = 0;					\
90 	       _FP_FRAC_SRL_8_i < 7-_FP_FRAC_SRL_8_skip;		\
91 	       ++_FP_FRAC_SRL_8_i)					\
92 	    X##_f[_FP_FRAC_SRL_8_i]					\
93 	      = ((X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip]		\
94 		  >> _FP_FRAC_SRL_8_down)				\
95 		 | (X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip+1]	\
96 		    << _FP_FRAC_SRL_8_up));				\
97 	  X##_f[_FP_FRAC_SRL_8_i++] = X##_f[7] >> _FP_FRAC_SRL_8_down;	\
98 	}								\
99       for (; _FP_FRAC_SRL_8_i < 8; ++_FP_FRAC_SRL_8_i)			\
100 	X##_f[_FP_FRAC_SRL_8_i] = 0;					\
101     }									\
102   while (0)
103 
104 
105 /* Right shift with sticky-lsb.
106    What this actually means is that we do a standard right-shift,
107    but that if any of the bits that fall off the right hand side
108    were one then we always set the LSbit.  */
109 #define _FP_FRAC_SRS_8(X, N, size)					\
110   do									\
111     {									\
112       _FP_I_TYPE _FP_FRAC_SRS_8_up, _FP_FRAC_SRS_8_down;		\
113       _FP_I_TYPE _FP_FRAC_SRS_8_skip, _FP_FRAC_SRS_8_i;			\
114       _FP_W_TYPE _FP_FRAC_SRS_8_s;					\
115       _FP_FRAC_SRS_8_skip = (N) / _FP_W_TYPE_SIZE;			\
116       _FP_FRAC_SRS_8_down = (N) % _FP_W_TYPE_SIZE;			\
117       _FP_FRAC_SRS_8_up = _FP_W_TYPE_SIZE - _FP_FRAC_SRS_8_down;	\
118       for (_FP_FRAC_SRS_8_s = _FP_FRAC_SRS_8_i = 0;			\
119 	   _FP_FRAC_SRS_8_i < _FP_FRAC_SRS_8_skip;			\
120 	   ++_FP_FRAC_SRS_8_i)						\
121 	_FP_FRAC_SRS_8_s |= X##_f[_FP_FRAC_SRS_8_i];			\
122       if (!_FP_FRAC_SRS_8_down)						\
123 	for (_FP_FRAC_SRS_8_i = 0;					\
124 	     _FP_FRAC_SRS_8_i <= 7-_FP_FRAC_SRS_8_skip;			\
125 	     ++_FP_FRAC_SRS_8_i)					\
126 	  X##_f[_FP_FRAC_SRS_8_i]					\
127 	    = X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip];		\
128       else								\
129 	{								\
130 	  _FP_FRAC_SRS_8_s						\
131 	    |= X##_f[_FP_FRAC_SRS_8_i] << _FP_FRAC_SRS_8_up;		\
132 	  for (_FP_FRAC_SRS_8_i = 0;					\
133 	       _FP_FRAC_SRS_8_i < 7-_FP_FRAC_SRS_8_skip;		\
134 	       ++_FP_FRAC_SRS_8_i)					\
135 	    X##_f[_FP_FRAC_SRS_8_i]					\
136 	      = ((X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip]		\
137 		  >> _FP_FRAC_SRS_8_down)				\
138 		 | (X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip+1]	\
139 		    << _FP_FRAC_SRS_8_up));				\
140 	  X##_f[_FP_FRAC_SRS_8_i++] = X##_f[7] >> _FP_FRAC_SRS_8_down;	\
141 	}								\
142       for (; _FP_FRAC_SRS_8_i < 8; ++_FP_FRAC_SRS_8_i)			\
143 	X##_f[_FP_FRAC_SRS_8_i] = 0;					\
144       /* Don't fix the LSB until the very end when we're sure f[0] is	\
145 	 stable.  */							\
146       X##_f[0] |= (_FP_FRAC_SRS_8_s != 0);				\
147     }									\
148   while (0)
149 
150 #endif /* !SOFT_FP_OP_8_H */
151